1. Field of the Invention
This invention relates to height gauges, and more particularly to a height gauge having a simplified construction and capable of allowing a slider to be zero set on a support in a desired position.
2. Description of the Prior Art
There has heretofore been widely used a so-called direct reading type height gauge wherein a main graduated scale is put on a support erected on a base, and a movement value of a slider movably supported by this support is read from the main graduated scale. While the direct reading type height gauge of the type described is simplified and tough in construction and low in cost, disadvantages have been presented that when conversion of dimensions from one system to another is needed, and particularly, in the case of measuring a deviation value where the slider is vertically moved as referenced from a given value, there is a possibility of causing confusion in the conversion, thus resulting in inconvenience in handling.
On the other hand, to obviate the inconvenience in handling as described above, a height gauge has been used in which an accurately finished rack is provided on the support in place of the main graduated scale, and there is provided an electronic counter or a mechanical counter incorporating therein a rotary encoder driven by the aforesaid rack. The height gauge as described above is very convenient because it has a so-called zero-setting function capable of zero-setting a counter (an indicating portion) no matter what position on the support the slider takes. This height gauge presents such disadvantages that the construction is very complicated, the number of parts is increased, the cost is very high, problems are easily caused, and control and maintenance are difficult.